Such interminglings have been suspected in the past, but there's more: Neanderthals were probably not the only other Homo species early Homo sapiens mixed with.

These findings call into question the familiar story that modern humans left Africa around 100,000 years ago and swept aside all other Homo species as they made their way around the globe. "It was a very simple story," says João Zilhão at the University of Bristol, UK. "Its simplicity suggested it would not be true." A more likely scenario is that as H. sapiens migrated, they met and interbred with other Homo species that have all since died out.